20855713 has 4 divisors (see below), whose sum is σ = 20866240. Its totient is φ = 20845188.

The previous prime is 20855701. The next prime is 20855743. The reversal of 20855713 is 31755802.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20855713 - 2⁹ = 20855201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20855743) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1293 + ... + 6586.

It is an arithmetic number, because the mean of its divisors is an integer number (5216560).

Almost surely, 2^20855713 is an apocalyptic number.

It is an amenable number.

20855713 is a deficient number, since it is larger than the sum of its proper divisors (10527).

20855713 is an equidigital number, since it uses as much as digits as its factorization.

20855713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10526.

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 20855713 is about 4566.8055574986. The cubic root of 20855713 is about 275.2590968568.

The spelling of 20855713 in words is "twenty million, eight hundred fifty-five thousand, seven hundred thirteen".